Globo Product Options, Variant

By far and away the best value option app available on the Shopify store, and I have looked around quite a lot. User friendly, nice layout, not clunky. The conditional logic isn't perfect if you want to get crazy complex but can do just about 95% of what you'd need.

The fact that you get all the features you do at the price you do is invaluable. Globo is awesome. Just please don't raise prices on us I enjoy using this app so much!!